Abstract: A light emitting structure has quantum wells grown on a coalesced substrate stemming from nanocolumns. The crystal structure is very low in defects and efficiency of light production is good. By growing the nanocolumns at a lower temperature, the quantum well structure is better matched to the coalesced substrate and efficiency is improved.

Abstract: Circuitry for controlling current between a load and a power supply, the circuitry comprising: an output stage comprising: an input node configured to be coupled to the power supply; and an output node configured to be coupled to the load; and one or more control nodes for controlling a conduction path between the input node and the output node; and protection circuitry coupled to the one or more control nodes, the protection circuitry configured to break the conduction path between the input node and the output node when a load voltage at the output node exceeds a supply voltage at the input node, wherein the protection circuitry comprises: an active protection circuit configured to break the conduction path when the supply voltage exceeds an operational threshold of the active protection circuit; and a passive protection circuit configured to break the conduction path when the supply voltage is below an operation threshold of the active protection circuit.

Abstract: The present disclosure relates to self-test circuitry for a system that includes one or more current control subsystems, each current control subsystem having a load terminal for coupling the current control subsystem to a load. The self-test circuitry comprises: a signal path associated with each current control subsystem, each signal path configured to selectively couple a measurement node to the load terminal of the current control subsystem, wherein the measurement node is common to all of the signal paths; voltage detection circuitry; and test voltage source circuitry configured to provide a test voltage to the measurement node. The voltage detection circuitry is operable to output a signal indicative of a fault condition if a voltage detected at the measurement node differs from the test voltage when the measurement node is coupled to the load terminal.

Abstract: The array of gallium-nitride (GaN) nanocolumns have quantum wells in a polar c-plane or in a semi-polar plane to emit light directed to ends of the nanocolumns and an interstitial filler material with light emitted in the nanocolumns being guided to exit from an end of the nanocolumns.

Abstract: The array of gallium-nitride (GaN) nanocolumns have quantum wells in a polar c-plane or in a semi-polar plane to emit light directed to ends of the nanocolumns and an interstitial filler material with light emitted in the nanocolumns being guided to exit from an end of the nanocolumns.

Abstract: The array of gallium-nitride (GaN) nanocolumns have quantum wells in a polar c-plane or in a semi-polar plane to emit light directed to ends of the nanocolumns and an interstitial filler material with light emitted in the nanocolumns being guided to exit from an end of the nanocolumns.

Abstract: Circuitry for controlling current between a load and a power supply, the circuitry comprising: an output stage comprising: an input node configured to be coupled to the power supply; and an output node configured to be coupled to the load; and one or more control nodes for controlling a conduction path between the input node and the output node; and protection circuitry coupled to the one or more control nodes, the protection circuitry configured to break the conduction path between the input node and the output node when a load voltage at the output node exceeds a supply voltage at the input node, wherein the protection circuitry comprises: an active protection circuit configured to break the conduction path when the supply voltage exceeds an operational threshold of the active protection circuit; and a passive protection circuit configured to break the conduction path when the supply voltage is below an operation threshold of the active protection circuit.

Abstract: The present disclosure relates to self-test circuitry for a system that includes one or more current control subsystems, each current control subsystem having a load terminal for coupling the current control subsystem to a load. The self-test circuitry comprises: a signal path associated with each current control subsystem, each signal path configured to selectively couple a measurement node to the load terminal of the current control subsystem, wherein the measurement node is common to all of the signal paths; voltage detection circuitry; and test voltage source circuitry configured to provide a test voltage to the measurement node. The voltage detection circuitry is operable to output a signal indicative of a fault condition if a voltage detected at the measurement node differs from the test voltage when the measurement node is coupled to the load terminal.